How to Measure Your Pond

Posted on May 16, 2018

Pond Volume Calculations

A common issue that customers have when they are trying to decide which pond pump, filter and aerators to use in their pond is how to measure their ponds. You may have been taught these calculations at school, but you didn't imagine you would have a fish pond then and certainly didn't pay attention! Here is a simple guide to help you measure your pond accurately enough to work out the capacity of your pond in litres.

Rectangular Ponds

Length (A) x Width (B) x Depth (C) = Volume (m3)

Volume (m3) x 1000 = Litres Capacity

Triangular Pond

(Length (A) x Width (B) x Depth (C)) ¸ 2 = Volume (m3)

Volume (m3) x 1000 = Litres Capacity

Circular Pond

Diameter (A) x Diameter (A) x 3.14 = Surface Area (m2)

Surface Area (m2) x Depth (B) = Volume (m3)

Volume (m3) x 1000 = Litres Capacity

Kidney Shaped Pond

Measure average depth:

Measure 6 depths (D) across the pond and record.

(D1 + D2 + D3 + D4 + D5 + D6) / 6 = Average Depth.

Measure average width:

Width (A) + Width (B) / 2 = Average Width

Use following equation to calculate volume:

Longest Length (C) x Average Width x Average Depth = Volume (m3)

Volume (m3) x 1000 = Litres Capacity

Additional Factors

If the average depth of the pond is 0.7m or less and/or is in full sunlight the system must be dimensioned larger to cope with additional algae produced from this type of pond.